This application relates to self-locating the position of a mammal body in Earth-based coordinates, referenced to the ground, when propelled by muscular support members, and the motion of that position over time for use in navigation and health assessment.
This application describes a geolocation system for mounting on a mammal that includes simple sensing sleeves on the calves of the body support members (e.g. legs), combined with an accelerometer-based gravity direction and force sensing at the center of mass of the body. The system is connected to a digital processing unit and a battery power supply to integrate the sensing to determine kinetic and potential energy of the body locomotion over time in a method that integrates out the aperiodic motion of the body about the center of mass, and uses the residual motion to measure the center of mass locomotion from a known point. This system is placed at the mammal center of mass which, for humans, is near the small of the back.
The calf sensing includes measurement of movement in the projected Earth's magnetic field onto the cylindrical sleeve axis with interwoven magneto-resistive strips, and also measures the muscular force exerted by the calf through elastic expansion and contraction of the sleeve with interwoven, elastic-resistive strips. The system can incorporate a GPS system for continuous motion measurement, to be used for calibration of the locomotion when GPS satellite data is available, and to establish the initiation geolocation point when beginning operation in GPS-denied regions, such as in buildings, caves, and urban environments. The geolocation method combines the GPS available body movement data with the sleeve and gravity sensing data through a neural-network, nonlinear mapping function, which removes the effects of the aperiodic, nonlinear locomotion, and leaves the residual movement for determining geolocation through a Lagrangian representation of the Equations of Motion (EOM). The Lagrangian EOM is the change in the difference between the human locomotion energy of potential changes with respect to the gravitational field, and kinetic changes with respect to leg-thrust forces. This balance process of basic human navigation, sensing tilt (statocyst as gravity) and rotation (canal as angular acceleration), is measured in synchronization over time to determine locomotion center-of-mass changes in position.
The system can be embodied for many applications, such as in GPS-denied navigation for soldier training in Military Operations in Urban Terrain (MOUT), for firefighters operating in buildings, for policemen on foot operating in cities, for personnel movement in caves, and for animal location and movement monitoring, such as for domestic animals and race horses. The system can also be used in determining small changes in balance, separate from the normal locomotion, by using a GPS/INS (inertial navigation system) system to calibrate the central motion, and where the “unbalance” about-center-of-mass motion can be a precursor to subtle medical changes in older humans.